1. Slippery when wet: Overview and comparison of Methods 537, ASTM D7579 and D7968
William Lipps, Brahm Prakash
Shimadzu Scientific Instruments, Inc. Columbia MD
August, 2017

2. ESI
standard
What is LCMSMS?

3. Liquid Chromatograph/Mass Spectrometer enables injection of water miscible phases and detection by mass
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
Polar Molecules
No Derivatization
Qualitative
Quantitative
Incomplete Separation
646 Pesticides in 10.5 minutes

4. LCMS Ionization introduces “molecular ion” into mass spectrometer
ESI
standard

5. A triple quadrupole is two mass spectrometers with a collision cell
MRM Q1 Q3
CID
Collision Cell
M5+
M1+
M2+
M3+
M4+
m3+
m2+
m1+
SIM
Fragment

6. The collision cell fragments the molecular ion
Q1:SIM
(at precursor mass)
m/z 609
Q3:Scan
Q2:Fragment
Product ion spectrum of Reserpine
195
397
Structure of Reserpine
609 N
m/z 195 O H N H H
Q3 m/z O H O O O O O O
m/z 397 O

7. Recent Improvements in LC result in sharp, narrow peaks and rapid run times
Narrow peak widths result (as low as 1 second)
Operating pressures as high as 19,000 psi
5 µM
particle size
1.7 µM
particle size

8. Modern Mass spectrometers combined with new LC technology enables high precision and short run times
6.25
6.30
6.35
6.40
6.45
6.50
6.55
6.60
6.65
6.70
6.75
6.80
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
Separation of 25 pesticides by mass

9. ESI
standard
Why run PFC’s

10. The EPA has issued a health advisory for Perfluorinated Compounds in drinking water

11. What is a health advisory?
Health Advisories (HAs) provide information on contaminants that can cause human health effects and are known or anticipated to occur in drinking water.
EPA's HAs are non-enforceable and provide technical guidance to states agencies and other public health officials on health effects, analytical methodologies, and treatment technologies associated with drinking water contamination.

12. Meet federal monitoring requirements
Laboratories supporting public water systems must use EPA-approved analytical methods when analyzing samples to:
Meet federal monitoring requirements
Demonstrate compliance with drinking water regulations

13. Perfluorinated Compounds are measured by HPLC-MSMS using EPA or ASTM methods

14. Non- Drinking Water PFCs

15. Military bases with PFC detections

16. Wastewater and wastewater treatment

17. Land applied biosolids

18. Overview of Methods

19. SPE- Extraction Technique

20. What Method 537 is: Solid Phase Extraction DRINKING WATER method
Internal Standard Calibration
ESI LCMSMS

21. What Method 537 is not: “Direct Injection” “Isotope Dilution”
Automated SPE
Wastewater or Solid Waste Method

22. Method 537: Problems / Implementation Suggestions
General:
Variable, analyte dependent, recovery
Method recommends use of a polypropylene transfer tube system to transfer the sample directly from the sample container to the SPE cartridge. 
Must rinse sample bottle  must extract entire 250 ml

23. Method 537: Problems / Implementation Suggestions
Laboratory and field blank contamination:
Many lab supplies and equipment can contain PFAAs.
Section requires a field reagent blank (FRB), Sampler must open the shipped FRB in the field and pour the preserved reagent water into the empty shipped sample bottle and seal the FRB. Ensures PFAAs were not introduced into the sample during sample collection/handling or from preservatives and bottles.

24. Method 537: Problems / Implementation Suggestions
Polypropylene (PP) vials/caps are necessary to prevent contamination of the sample from PTFE coated septa.
PP caps do not re-seal, so evaporation occurs after injection.
Multiple injections from the same vial are not possible.
Suggest splitting extract before injection
PFAAs can build up in the PTFE solvent transfer lines on the LC during
inactivity (Polytetrafluoroethylene)
Recommend replacing PTFE lines with PEEK (polyetheretherketone)tubing
Recommend replacing PTFE solvent frits with stainless steel frits

25. ASTM D7979 is a “Direct Inject” Method
Shimadzu app note No.C81

26. Separates PFCs with LC then measures by MSMS

27. Eliminates reagent contamination with a delay column

28. SPE direct inject Method EPA 537 D7979 D7968 Validation UCMR3
(ORD)
Single Lab
(Region V and ASTM)
Single lab
Extraction
SPE
250 ml  1 ml
Dilute 5 ml with 5 ml MeOH, Filter,
direct inject
Extract 2 g with 10 ml (1+1) MeOH
Holding time
Extract in 14 analyze in 28 days
5g/L Trisma ≤ 6°C
28 days
≤ 6°C

29. EPA 537 Extraction procedure
250 ml
250 ml
Surrogate
10 ml/Minute
4 ml MeOH
Elute

30. EPA 537 Extraction procedure
LCMS-8040
1 ml 96% MeOH
Internal Standard
Evaporate

31. ASTM D7979 Extraction procedure
5 ml Sample
Surrogate
5 ml MeOH

32. ASTM D7979 Extraction procedure
LCMS-8060
10 µL Acetic Acid

33. ASTM D7968 Extraction procedure
20 µL NH4OH
2 g Sample
Surrogate
10 ml (1+1) MeOH

34. ASTM D7968 Extraction procedure
LCMS-8060
Tumble 1 hour
50 µL Acetic Acid

35. Comparison of method quantitation
EPA 537
D7979
D7968
Analytes
surrogates and 3 internal standards
surrogates
Quantitation Range
5 – 15 ng/L
(at 1/250)
Next slides
Quantitation IS ES

36. Comparison of matrices tested
Method
EPA 537
D7979
D7968
Matrix
Drinking Water
Water and sludge (≤ 0.2% Solids)
Soil
Matrices
Cincinnati tap, ground, surface
Reagent water, Chicago river water, POTW effluent, POTW influent, 2 POTW with overflow
Ottawa sand, Frederick sand, Annapolis clay, Vicksburg clay, Vicksburg silt

37. Quantitation range for D7979 – water (direct inject)
Analyte
Reporting Ranges
(ng/L)
PFTreA, PFTri, PFDoA, PFUnA, PFDA, PFNA, PFechS, PFOA, PFHxS, PFHpA, PFHxA, FOUEA, FHpPA, FHUEA
PFOS
PFBS
PFPeA, PFBA
FHEA, FOEA
FDEA

38. Quantitation range for D7968 – soil (2g/10ml)
Analyte
Reporting Ranges (ng/Kg)
PFTreA, PFTriA, PFDoA, PFUnA, PFDA, PFNA, PFechS, PFOA, PFHxS, PFHpA, PFBS, FOUEA, FHpPA, FHUEA
25 – 1000
PFOS, PFHxA
PFPeA, PFBA
125 – 5000
FHEA
600 – 20,000
FOEA
750 – 20,000
FDEA
500 – 20,000

39. Shimadzu LCMS-8060 ASTM D7979 (5 ng/L)

40. Comparison of Method calibration criteria
EPA 537
D7979
D7968
Calibration
≥ 5 points
5 – 9 points
Force through origin
yes no
Fit
RSE ≤ 30%
Asymmetry
0.8 – 1.5
Not required
Confirmation ion
if available

41. Comparison of Method batch QC criteria
EPA 537
D7979
D7968
Batch size
≤ 20 samples
≤ 30 samples
Blank
≤ 1/3 MRL
≤ ½ “RLCS”
MRL
50 – 150 %
35 – 150% IS
< 50% Area Drift
Not required
Surrogate recovery
70 – 130 %
RLCS = Reporting Limit Control Standard

42. Comparison of sample specific batch QC criteria
Method
EPA 537
D7979
D7968
MS/MSD recovery
70 – 130 %
RPD
≤ 30 %

43. Summary for the three US methods
EPA 537
ASTM D7979
ASTM D7968
Drinking Water
Wastewater
Sludge and Solids

44. Triple Quad LCMS Products
2015
ASTM
2013
2-3 times more sensitive
Scanning Speed 30,000 u/sec
Polarity Switching Rate 5 msec
60000
Signal to Noise Ratio: 1 pg of Reserpine
2012
Scanning Speed: 15,000 u/sec
Polarity Switching Rate: 15 msec
10000
2010
EPA 537
2000

45. ASTM D7979 ASTM D7968 EPA 537 Throughput
Equipment, Standard and Labor Cost

46. Thank you